Driven by government deregulation of telecommunications services and the rapid introduction of new telecommunications networking technologies, the telecommunications industry has experienced unprecedented growth and change in recent years. The increasing demand for distributed computing systems and instant availability of online services and information has made access to reliable high-speed telecommunications networks essential to the daily activities of corporate enterprises and individuals alike. To meet the demand for the latest technology and additional capacity, literally hundreds of telecommunications vendors now compete with each other in the marketplace for telecommunications solutions, offering a large variety of services and technologies, some offered as propriety, some offered as "standard," and some offered as "quasi-standard."
As competition among telecommunications vendors has grown, so has the size, complexity and heterogeneity of modern telecommunications networks. These complex heterogeneous telecommunications networks, which may span thousands of miles of territory, can--and frequently do--contain thousands of different network elements of various types, made by different manufacturers, and using different communications protocols.
Managing these large, complex and heterogeneous telecommunications networks presents substantial challenges. For each network element, a network manager needs to know whether the elements are operating properly and what are the nature and severity of any problems. For most networks, it is highly desirable to obtain this information at a network management facility without having to dispatch personnel to the physical location of the network element. Systems that provide this information from a network element to a network management center, usually by telecommunications links, are known as element management systems ("EMSs"). Once management information regarding a network element is transmitted to the network management center, the network manager can analyze the information and direct corrective or other appropriate action. Once again, it is desirable for at least certain actions--such as shutting down an overheating radio before it burns itself out, or rerouting traffic away from a malfunctioning multiplexer--that the action be taken at the network element site as the result of a command transmitted from a remote network management center. Similarly, it is desirable, to the extent possible, to control and configure network elements remotely from the physical location of the individual elements. EMSs are used for these purposes, as well.
Network elements of different types, such as radios and multiplexers, typically require separate EMSs, even if they are manufactured by the same company. Historically, an EMS for a particular network element could only be obtained from the element's vendor, usually at a substantial price. If, for example, a telecommunications network contains four different models of digital radios, the network administrator typically has to purchase and support four different EMSs, even if all the radios are from the same manufacturer. Thus, managing a telecommunications network containing network elements of different types, different protocols and different manufacturers is almost always costly.
In addition, different manufacturers frequently use different protocols and commands for managing their network elements. Often, the same manufacturer uses different protocols and commands for different types of equipment that it manufactures. Indeed, even when a manufacturer claims to use a "standard" protocol for managing network elements (such as Q3, TL-1 or SNMP), it is not uncommon for that manufacturer to implement that protocol differently from other manufacturers. Moreover, documentation for a specific EMS and a specific network element may be unavailable, incomplete, out-of-date or incorrect. Hardware and software have bugs and limitations which also must be addressed.
As a consequence of these and other problems, the expertise required to program, manage and troubleshoot a particular EMS for a particular type of network element made by one manufacturer is ordinarily of limited use when it comes to programming, managing and troubleshooting a different EMS for a different type of network element or even the same type of network element made by a different manufacturer. Thus, people who become experts at supporting particular EMSs and network elements ordinarily cannot efficiently apply those skills to supporting other EMSs or other types of network elements.
It is therefore not uncommon for a single operator to maintain separate teams of experts for each type of network element in its telecommunications network. Network administrators who have already invested substantial sums of money in purchasing separate EMS systems for a variety of network elements, potentially made by different manufacturers, may also have to invest substantial sums of money and resources to develop and maintain the expertise required to support each type of network element made by each manufacturer.
Network administrators trying to reduce the costs associated with employing separate teams of expert programmers for each type of network element have attempted to purchase and use commercial off-the-shelf telecommunications network management solutions to manage their network elements. These management solutions, however, can be extremely expensive, frequently support only certain network elements, and can require extensive system integration and customization efforts. Consequently, a network administrator using a commercial off-the-shelf network management application often still has to purchase separate commercial off-the-shelf applications for each type of network element, or for each manufacturer of network elements used in the telecommunications network.
Moreover, most commercial off-the-shelf network management solutions are geared towards the "legacy" architectures of older telecommunications network management solutions. These legacy-based solutions frequently do not support the more recent protocols, such as CORBA and Q3, or do not support a particular manufacturer's implementation of the more recent protocols, without expensive modifications. Indeed, some legacy-based solutions may require the network administrator to change the methodology of managing the entire telecommunications network.
In addition, due in large part to the problems discussed above, many commercial element management systems available today lack scalability. Each time an organization or network administrator wants to add a new type of network element to the telecommunications network, or to start using a new manufacturer, a new team of experts or a new network management application, or both, must also be added. This also usually means that the organization or network administrator must be prepared to take on a large and expensive integration effort, adding further to the costs and complexity of upgrading the network.
Another problem faced by telecommunications network administrators today is that commercial or third-party EMSs may not provide the level of flexibility required for certain telecommunications network applications. For example, if a telecommunication network requires new or custom user interfaces, new functionality or new reporting capabilities, many commercial EMSs lack the flexibility to deploy such new or customized applications easily and inexpensively.
Accordingly, today's telecommunications network administrators are frequently captive to the type and manufacturers of network elements utilized in their current network. Often, the manufacturer and type of network elements already present in the network effectively determine which type of network elements can be added to the network, or from which manufacturer new network elements can be obtained, what kind of expertise must be obtained to manage the new network elements and which brand of network management software can be used. Once deployed, networks and their management solutions must be supported for many years if the organization has any hope of recouping the substantial initial investments required. This often leads telecommunications network managers to conclude that they have lost control over the growth and development of their own telecommunications networks. This lack of control severely restricts an organization's ability to expand or modify its network, integrate new technology and respond in a timely manner to their organizations telecommunications requirements.
In an attempt to begin to address some of these problems, the International Telecommunications Union ("ITU") promulgates a set of telecommunications specifications known as Telecommunications Management Network ("TMN") standards. The TMN standards defines relationships between basic network building blocks (i.e., different network elements, different network protocols and different network management applications) in terms of standard interfaces.
The TMN standards defines five major functional areas for network management systems, based on key activities performed by network management personnel, including:
Fault Management--including trouble management, corrective actions for service, fault reporting and recovery; PA1 Configuration Management--including resource provisioning (timely deployment of resources to satisfy expected service demands), service provisioning (assigning services and features to end-users), and configuration of equipment and resources; PA1 Performance Management--including processes that insure the most efficient utilization of network resources and their ability to meet service demands, and collection, correlation, and analysis of data regarding the service performance of network resources; PA1 Security Management--including control of access to and protection of both the network and network management systems against intentional and accidental abuse, unauthorized access, and communications loss; and PA1 Accounting Management--including processes that maintain customer billing as well as resource inventory. PA1 Network Element Layer--This layer typically provides the interface for managing the NE itself. PA1 Element Management Layer--This layer provides capabilities provide for managing multiple network elements usually of the same type or manufacturer. Typically, this layer emphasizes fault management, configuration management, performance management and security for the NEs. PA1 Network Management Layer--This layer provides network management for a full network, including circuit configuration, performance, and fault management, as well as provisioning of bandwidth. PA1 Service Management Layer--This layer provides for network management of the services provided by the network, such as inventory (accounting management) of bandwidth and services. PA1 Business Management Layer--This layer provides for network management of billing, service allocation, and other business aspects of the network.
The TMN architecture provides for a division of management capabilities according to layers. Each layer provides a set of the functional elements (that is, Fault, Performance, Configuration, Security, and Accounting Management). Not all functional elements are required at each layer. The TMN Layers (from bottom to top) are:
A wide variety of protocols (e.g., Q3, CORBA, SNMP and TL-1) is used as the communications media between TMN layers. The Q3 protocol is widely used in Europe and Asia as the network management protocol of choice for numerous network elements--especially transport networks, that is, networks that transfer information at very high speeds using fiber optic and digital microwave radio. Q3 has also seen a surge of activity in the United States, especially in Synchronous Optical Network ("SONET") and Dense Wave Division Multiplexing ("DWDM") deployments. Toolkits to build applications using Q3 are supplied by companies such as Vertel, DSET Corporation, HP, and Sun Microsystems.
In the telecommunications network management industry, the Common Object Request Broker Architecture ("CORBA") is increasingly being used for integration of telecommunications software applications and NEs. Essentially, CORBA is a specification for an object-oriented architecture for distributed applications. CORBA implementations are provided by a number of companies, the most widely deployed is called Orbix.TM. from IONA Technologies.
SNMP, or Simple Network Management Protocol, is a simple protocol for managing TCP/IP (or Internet-based) computer networks. SNMP is widely deployed as a management protocol for routers, bridges and other computer-network related devices. In recent years, SNMP has been extended as a management protocol for many telecommunications network elements, most specifically, ATM (Asynchronous Transfer Mode) switches and routers. The SNMP protocol is in the public domain, consequently, there are numerous deployments and implementations.
TL-1 is by far the most widely used protocol in telecommunications management. Most of today's transport network elements deploy TL-1 as the management protocol. Although there is some standardization to TL-1, most vendors implement either a subset or superset of the TL-1 commands.
Accordingly, there is a need for flexible and scalable element management systems for telecommunications networks that can monitor and manage very large, heterogeneous telecommunications networks and support rapid, low-cost integration of new and different network element types having a variety of protocols and a variety of manufacturers.